brakes MERCEDES-BENZ ML320 1997 Complete Owner's Guide

170
Automatic transmission
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Press and hold selector lever in the ædirection:
The transmission will shift from the current gear
directly to gear range “D”.
Important!
With transmission in gear range “D”, “4” or “3”,
upshifting from 1st to 2nd to 3rd gear is delayed
depending on vehicle speed and engine temperature.
This allows the catalytic converter to heat up more
quickly to operating temperatures. During the brief warm-up period this delayed upshift
and increased engine noise might be perceived as a
malfunction. However, neither the engine nor
transmission are negatively affected by this mode of
operation.
The delayed upshift is effective with vehicle speeds
below 31 mph (50 km / h) at partial throttle and engine
temperatures below 95 °F (35 °C).
To avoid overrevving the engine when the selector lever
is moved to a lower gear range, the transmission will not
shift to a lower gear, if the engine’s revolutions per
minute limit would be exceeded. In this case there will
be no downshift, even when the vehicle speed reaches
the engine’s RPM limit of that gear, e.g. by applying the
service brakes. Continue driving in the usual manner.
The transmission will then shift down automatically.
To prevent the engine from laboring at low RPM when
driving uphill gradients or with your vehicle heavily
loaded, the automatic transmission will downshift when
necessary to maintain engine RPM within the best
torque range.
Wa r n i n g !
On slippery road surfaces, never downshift in order
to obtain braking action. This could result in drive
wheel slip and reduced vehicle control. Your
vehicle’s ABS will not prevent this type of loss of
control.

175
Driving instructions
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Power assistance
Brakes The condition of the parking brake system is checked
each time the vehicle is in the shop for the required
maintenance service.
If the parking brake is released and the brake warning
lamp in the instrument cluster stays on and there is no
audible warning (EBP), the brake fluid level in the
reservoir is too low.
Brake pad wear or a leak in the system may be the
reason for low brake f luid in the reservoir.
Have the brake system inspected at an authorized
Mercedes-Benz Light Truck Center immediately.
All checks and service work on the brake system should
be carried out by an authorized Mercedes-Benz Light
Truck Center.
Install only brake pads and brake fluid recommended by
Mercedes-Benz.
Wa r n i n g !
When the engine is not running, the brake and
steering systems are without power assistance.
Under these circumstances, a much greater effort is
necessary to stop or steer the vehicle.Wa r n i n g !
After driving in heavy rain for some time without
applying the brakes or through water deep enough
to wet brake components, the first braking action
may be somewhat reduced and increased pedal
pressure may be necessary to obtain expected
braking effect. Be sure to maintain a safe distance
from vehicles in front.Resting your foot on the brake pedal will cause
excessive and premature wear of the brake pads.It can also result in the brakes overheating thereby
significantly reducing their effectiveness. It may
not be possible to stop the vehicle in sufficient time
to avoid an accident.
Wa r n i n g !
If other than recommended brake pads are
installed, or other than recommended brake fluid
is used, the braking properties of the vehicle can be
degraded to an extent that safe braking is
substantially impaired. This could result in an
accident.

176
Driving instructions
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Caution!
When driving down long and steep grades, relieve the
load on the brakes by shifting into a lower gear to use
the engine’s braking power. This helps prevent
overheating of the brakes and reduces brake pad wear.
After hard braking, it is advisable to drive on for some
time, rather than immediately parking, so the air stream
will cool down the brakes faster.
Driving off
Apply the service brakes to test them briefly after
driving off. Perform this procedure only when the road
is clear of other traffic.
Warm up the engine smoothly. Do not place full load on
the engine until the operating temperature has been
reached.
When starting off on a slippery surface, do not allow one
drive wheel to spin for an extended period with the ESP
switched off. Doing so may cause serious damage to the
drive train which is not covered by the Mercedes-Benz
Limited Warranty. Parking
Important!
It is advisable to set the parking brake whenever
parking or leaving the vehicle. In addition, move
selector lever to position “P”.
When parking on hills, always set the parking brake.
Wa r n i n g !
To reduce the risk of personal injury as a result of
vehicle movement, before
turning off the engine
and leaving the vehicle, always:
1. Keep right foot on the service brake pedal.
2. Firmly depress parking brake pedal.
3. Move the selector lever to position “P”.
4. Slowly release the service brake pedal.
5. Turn front wheels towards the road curb.
6. Turn the key to steering lock position 0 and remove.
7. Take the key and lock vehicle when leaving.

178
Driving instructions
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Specified tire pressures must be maintained. This
applies particularly if the tires are subjected to high
loads (e.g. high speeds, heavy loads, high ambient
temperatures).
Aquaplaning
Depending on the depth of the water layer on the road,
aquaplaning may occur, even at low speeds and with
new tires. Reduce vehicle speed, avoid track grooves in
the road and apply brakes cautiously in the rain. Tire traction
The safe speed on a wet, snow covered or icy road is
always lower than on a dry road.
You should pay particular attention to the condition of
the road whenever the outside temperatures are close to
the freezing point.
We recommend M+S rated radial-ply tires with a
minimum tread depth of approximately 1/8 in (4 mm)
for the winter season for all four wheels to insure
normal balanced handling characteristics. On packed
snow, they can reduce your stopping distance as
compared with summer tires. Stopping distance,
however, is still considerably greater than when the
road is not snow or ice covered.
Wa r n i n g !
Do not drive with a flat tire. A flat tire affects the
ability to steer or brake the vehicle. You may lose
control of the vehicle. Continued driving with a flat
tire or driving at high speed with a flat tire will
cause excessive heat build-up and possibly a fire.
Wa r n i n g !
If ice has formed on the road, tire traction will be
substantially reduced. Under such weather
conditions, drive, steer and brake with extreme
caution.

183
Driving instructions
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Off-Road driving
Familiarize yourself with the vehicle characteristics and
gear changing before you attempt any difficult terrain
off-road driving. We recommend that you start out with
easy off-road travel.
Please read this chapter carefully before you begin
off-road travel.
Special driving features are available for specific kinds
of operation:
• LOW RANGE mode, see page 209
• LOW RANGE - ABS, see page 202
• LOW RANGE - 4-ETS+, see page 204
• LOW RANGE - ESP, see page 208
Engage the LOW RANGE mode before driving under
off-road conditions. For switching LOW RANGE mode on
and off see page 209.
Fasten items being carried as securely as possible, see
page 136.
We recommend to keep doors, liftgate, windows, and
roof closed whenever driving in off-road mode. Important!
Adjust vehicle speed to condition of terrain. The more
uneven, rutty and steeper the terrain, the lower the
speed should be.
Watch out for obstacles, such as rocks, holes,
tree-stumps, ruts.
Be especially careful when driving in unknown
territory. Eventually get out of the vehicle and scout the
path you intend to take.
Continuous and speedy driving in sandy soil overcomes
the vehicle rolling resistance, and helps to prevent the
vehicle from sinking into the ground.
Do not initiate jumps with the vehicle. It interrupts the
forward momentum of the vehicle.
Sand, dirt, mud and other material having friction
property, can cause exceptional wear and tear as well as
failure of the brakes.
In this case the brakes may be less effective or even fail
when you most need them. Always clean and check the
brakes following each off-road trip.

185
Driving instructions
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Driving on embankments, slopes and other steep
inclines should only be done straight up or downhill, i.e.
in the line of gravity.
Do not drive along the side of a slope (danger of vehicle
rollover). If in doing so, the vehicle begins to show a
tendency to roll, immediately steer into a line of gravity
(straight up or downhill).
To help avoid the vehicle rolling over, never turn it
around on steep inclines. If the vehicle cannot complete
the attempted climb, back it down in reverse gear.
Utilize the engine’s braking power when descending a
slope, observe the engine speed (do not overrev the
engine). Apply the service brake as needed.
Check the brakes after a lengthy downgrade drive.
Notes:
Avoid excessive engine speeds – drive with moderate
engine speeds (max. 3000 RPM).
Select gear range “2” or “1” on the automatic
transmission, see page 165. Traction in steep terrain:
Be easy on the accelerator and watch for continuous
wheel traction when driving in steep terrain.
The 4-ETS+ helps greatly when starting out on a steep
incline. The front wheels have then the tendency to slip
due to the weight reduction over the front axle. The ETS
recognizes the situation and limits the torque for the
front wheels by braking them. Simultaneously the
torque for the rear wheels is increased.
See page 203 for four wheel electronic traction system
(4-ETS+).
Driving across a hilltop:
To prevent the vehicle from speeding up too much after
climbing a hill, decelerate just ahead of a hilltop (do not
select gear range “N”). Use the momentum of the
vehicle to drive across the hilltop. Driving in this
manner prevents the vehicle from jumping across the
hilltop and thus loosing its forward momentum.

186
Driving instructions
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Driving downhill:
Select gear range “1” on the automatic transmission,
see page 165.
Drive downhill observing the same rules as driving
uphill.
Driving on embankments, slopes and other steep
inclines should only be done straight up or downhill, i.e.
in the line of gravity.
Do not drive along the side of a slope (danger of vehicle
rollover). If in doing so, the vehicle begins to show a
tendency to roll, immediately steer into a line of gravity
(straight up or downhill). Utilize the engine’s braking power when descending a
slope, observe the engine speed (do not overrev the
engine). Apply the service brake as needed.
The special low range ABS setting allows for precise and
brief (cyclical) blocking of the front wheels, permitting
them to dig into loose ground. Remember that the front
wheels when stopped, slide across a surface, thus loose
their ability to steer the vehicle.
Check the brakes after a lengthy downgrade drive.
Important!
Only apply the service brake if the vehicle travels
straight downhill, i.e. in the line of gravity.

187
Driving instructions
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Driving through water
1 20 in (50 cm)
Before driving through water, determine its depth. It
should not be deeper than approximately
20 inches (50 cm). Switch to LOW RANGE mode before driving through
water.
Switch off the exterior lamps as well as the climate
control.
Enter the water only at a shallow spot. Never take a
running start. Drive slowly, avoiding a bow wave.
Do not stop vehicle immersed in water, and do not shut
off the engine.
To dry the brakes, apply pressure to the brake pedal
several times after leaving the water.

189
Driving instructions
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Returning from off-road driving
Off-road driving increases strain on the vehicle.
We recommend that you inspect the vehicle for possible
damage after each off-road trip. Recognizing any
damage and a subsequent timely repair reduces the
chance of a possible breakdown or accident later on.
Proceed as follows:
• Switch off the LOW RANGE mode, see page 209.
• Remove excessive dirt from tires, wheels, wheel
housings, and underbody. For instance, after driving
in mud, clean the radiator, chassis, engine, brakes,
and wheels from extreme dirt, using a strong jet of
water.
• Inspect frame, oil pan, brake hoses, etc., as well as
vehicle underbody for possible damage.
• Check tires for possible damage, clean all exterior
lamps, and conduct a brake test. •
Check for brush or branches caught in the
undercarriage. They could increase the possibility of
a fire, as well as cut fuel and / or brake lines,
puncture rubber bellows of the axles or drive shafts.
Wa r n i n g !
If you feel a sudden significant vibration or ride
disturbance, or you suspect that possible damage to
your vehicle has occurred, you should turn on the
hazard warning flashers, carefully slow down, and
drive with caution to an area which is a safe
distance from the roadway.Inspect the tires and under the vehicle for possible
damage. If the vehicle or tires appear unsafe, have
it towed to the nearest Mercedes-Benz Light Truck
Center or tire dealer for repairs.

193
Driving instructions
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Attaching a trailer
Please observe maximum permitted trailer dimensions
(width and length).
Most states and all Canadian provinces require safety
chains between your tow vehicle and the trailer. The
chains should be crisscrossed under the trailer tongue.
They must be attached to the hitch receiver, and not to
the vehicle’s bumper or axle. Be sure to leave enough
slack in the chains to permit turning corners.
Most states and all Canadian provinces require a
separate brake system at various trailer weights. Caution!
Do not connect a trailer brake system (if trailer is so
equipped) directly to the vehicle’s hydraulic brake
system, as your vehicle is equipped with antilock
brakes. If you do, neither the vehicle’s brakes nor the
trailer’s brakes will function properly.
The provided vehicle electrical wiring harness for trailer
towing has a brake signal wire (color orange) for
hook-up to a brake controller.
Most states and all Canadian provinces require a
break-away switch on trailers with a separate brake
system. The switch activates the trailer brakes in the
possible event that the trailer might separate from the
tow vehicle.
You should consider using a trailer sway control system.
For further information see your authorized
Mercedes-Benz Light Truck Center.